Information or data processors are found in many contemporary electronic devices such as, for example, personal computers, game playing devices and video equipment. Modern processors include extensive execution resources to support concurrent processing of multiple instructions. A processor typically includes several operational units including: integer, floating point, branch, and memory units. Additionally, register files and on-chip caches are also provided to supply the operational units with operands. This is particularly evident in graphics processors, which typically have a large number of operational units and registers compared to general purpose processors. When fully engaged by an executing program, these operational units can create significant power dissipation issues.
To conserve power, a processor may employ power throttling, such as by gating a clock signal to cut off the clock signal delivered to operational units that are not used by an executing instruction sequence. Alternately (or additionally), a processor may limit an operational unit's operating frequency by slowing the clock signal for that operational unit. Power throttling may also be implemented through altering the number of instructions processed by an operational unit per clock cycle (instruction throttling) or by suspending instruction issuance for an operational unit for a time period. These and other power control mechanisms have their particular advantages and disadvantages.